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Sometimes words fail

In the lab and on the screen, stuttering gets its close-up.

November 29, 2010|By Jessica Pauline Ogilvie, Special to the Los Angeles Times
  • An estimated 3 million American adults have a stutter that didn't resolve in childhood, according to the nonprofit Stuttering Foundation of America.
An estimated 3 million American adults have a stutter that didn't… (Ricardo DeAratanha / Los…)

Robin Sullivan was 10 when she first began looking for information about her stutter. She'd had the speech disorder for as long as she could remember — one of her earliest memories is of lying on a table practicing breathing exercises.

She wasn't bullied or teased, she says; she just felt ignored. "I went to the library, and I read everything I could get my hands on," she says. "I was looking for that feeling of not being alone."

It took Sullivan, now in her early 40s, until high school to find the help that she needed. "Up until then I felt out of control, helpless," she says.

An estimated 3 million American adults have a stutter that didn't resolve in childhood, according to the nonprofit Stuttering Foundation of America. As kids, many dealt with the giggles of classmates and confusion of teachers; as adults, they often deal with uncertain glances and the impatience of strangers. They've long sought comfort from each other, sharing their experiences at conferences and advocacy groups. Now, with the release of "The King's Speech," a critically acclaimed movie starring Colin Firth as King George VI, the so-called stuttering prince, many hope that the public will begin to comprehend their struggles.

There's no cure for stuttering — "I have good speech days and bad speech days," Sullivan says — but researchers and experts have made strides in understanding the complicated disorder. They've found versions of genes linked to stuttering risk; they've found differences in the brains of stutterers too. Both may offer clues to the roots of the speech block and, maybe, point the way toward medical therapies one day.

Stuttering affects about 1% of the adult population worldwide, and four times as many men as women. The disorder is classified by disruptions that happen during speech; people who stutter may alternately repeat part of a word multiple times, or be unable to produce sound at all.

"It's like time stops for a moment," says Sullivan of her own stutter. Her lips and face tense up, and even as she hears conversations and activity continuing around her, for the brief minute that her mouth refuses to form words, she's on the outside of it all. "You feel stuck," she says. "Just plain stuck."

As children first learn to speak, stuttering isn't unusual: Nearly 5% of kids around the age of 3 or 4 have trouble with fluency. In four out of five of those children, stuttering resolves on its own. It's unclear what causes the remaining children to retain the disorder, but experts believe that the answer may lie in family history.

In fact, approximately 60% of people who stutter have family members with the disorder, according to the Stuttering Foundation of America. And in a study published in the New England Journal of Medicine in February, government researchers uncovered the first genetic mutations that may be at the root of the problem for some. In a large family with a strong history of the disorder, mutations in one of three genes — known as NPTAB, GNPTG and NAGPA — were found in some affected participants.

Though it's progress, experts aren't sure how the three genes lead to stuttering, and the findings don't go far in explaining the disorder in the entire population.

"Mutations in these genes account for about 9%" of stuttering cases, estimates Dennis Drayna, a genetics researcher at the National Institute on Deafness and Other Communication Disorders, who co-authored the study. To make things more complicated, not everyone with the gene will develop a stutter, he adds.

Researchers are also looking for neurological differences in people who stutter. They've found several.

Among people who stutter, a number of brain regions responsible for movement control (including movement associated with speech) are overactive in the right hemisphere. Experts believe that this is a result

of the right hemisphere making up for a defect in the left. (In people who speak fluently, the left hemisphere is the dominant one for language.)

Parts of the left hemisphere "never fully develop" in stutterers, suggests Dr. Gerald Maguire, director of the Kirkup Center for the Medical Treatment of Stuttering at UC Irvine. "So the right hemisphere begins to compensate."

The longer a person stutters, Maguire adds, the more the right hemisphere compensates and the stronger the brain imbalance grows.

Scientists also believe that key differences between stutterers and non-stutterers lie in parts of the brain that compose what's called the basal ganglia. These structures, located toward the center of the brain, together play a complex role in the smooth timing and initiation of movements. Recent research has confirmed that the severity of stuttering correlates with the level of activity in the basal ganglia — and that this activity improves after participants undergo speech therapy.

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